Quelle  lt3651-charger.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0+
/*
 *  Driver for Analog Devices (Linear Technology) LT3651 charger IC.
 *  Copyright (C) 2017, Topic Embedded Products
 */

#include <linux/device.h>
#include <linux/gpio/consumer.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/slab.h>
#include <linux/of.h>

struct lt3651_charger {
 struct power_supply *charger;
 struct power_supply_desc charger_desc;
 struct gpio_desc *acpr_gpio;
 struct gpio_desc *fault_gpio;
 struct gpio_desc *chrg_gpio;
};

static irqreturn_t lt3651_charger_irq(int irq, void *devid)
{
 struct power_supply *charger = devid;

 power_supply_changed(charger);

 return IRQ_HANDLED;
}

static inline struct lt3651_charger *psy_to_lt3651_charger(
 struct power_supply *psy)
{
 return power_supply_get_drvdata(psy);
}

static int lt3651_charger_get_property(struct power_supply *psy,
  enum power_supply_property psp, union power_supply_propval *val)
{
 struct lt3651_charger *lt3651_charger = psy_to_lt3651_charger(psy);

 switch (psp) {
 case POWER_SUPPLY_PROP_STATUS:
  if (!lt3651_charger->chrg_gpio) {
   val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
   break;
  }
  if (gpiod_get_value(lt3651_charger->chrg_gpio))
   val->intval = POWER_SUPPLY_STATUS_CHARGING;
  else
   val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
  break;
 case POWER_SUPPLY_PROP_ONLINE:
  val->intval = gpiod_get_value(lt3651_charger->acpr_gpio);
  break;
 case POWER_SUPPLY_PROP_HEALTH:
  if (!lt3651_charger->fault_gpio) {
   val->intval = POWER_SUPPLY_HEALTH_UNKNOWN;
   break;
  }
  if (!gpiod_get_value(lt3651_charger->fault_gpio)) {
   val->intval = POWER_SUPPLY_HEALTH_GOOD;
   break;
  }
  /*
 * If the fault pin is active, the chrg pin explains the type
 * of failure.
 */
  if (!lt3651_charger->chrg_gpio) {
   val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
   break;
  }
  val->intval = gpiod_get_value(lt3651_charger->chrg_gpio) ?
    POWER_SUPPLY_HEALTH_OVERHEAT :
    POWER_SUPPLY_HEALTH_DEAD;
  break;
 default:
  return -EINVAL;
 }

 return 0;
}

static enum power_supply_property lt3651_charger_properties[] = {
 POWER_SUPPLY_PROP_STATUS,
 POWER_SUPPLY_PROP_ONLINE,
 POWER_SUPPLY_PROP_HEALTH,
};

static int lt3651_charger_probe(struct platform_device *pdev)
{
 struct power_supply_config psy_cfg = {};
 struct lt3651_charger *lt3651_charger;
 struct power_supply_desc *charger_desc;
 int ret;

 lt3651_charger = devm_kzalloc(&pdev->dev, sizeof(*lt3651_charger),
     GFP_KERNEL);
 if (!lt3651_charger)
  return -ENOMEM;

 lt3651_charger->acpr_gpio = devm_gpiod_get(&pdev->dev,
     "lltc,acpr", GPIOD_IN);
 if (IS_ERR(lt3651_charger->acpr_gpio)) {
  ret = PTR_ERR(lt3651_charger->acpr_gpio);
  dev_err(&pdev->dev, "Failed to acquire acpr GPIO: %d\n", ret);
  return ret;
 }
 lt3651_charger->fault_gpio = devm_gpiod_get_optional(&pdev->dev,
     "lltc,fault", GPIOD_IN);
 if (IS_ERR(lt3651_charger->fault_gpio)) {
  ret = PTR_ERR(lt3651_charger->fault_gpio);
  dev_err(&pdev->dev, "Failed to acquire fault GPIO: %d\n", ret);
  return ret;
 }
 lt3651_charger->chrg_gpio = devm_gpiod_get_optional(&pdev->dev,
     "lltc,chrg", GPIOD_IN);
 if (IS_ERR(lt3651_charger->chrg_gpio)) {
  ret = PTR_ERR(lt3651_charger->chrg_gpio);
  dev_err(&pdev->dev, "Failed to acquire chrg GPIO: %d\n", ret);
  return ret;
 }

 charger_desc = <3651_charger->charger_desc;
 charger_desc->name = pdev->dev.of_node->name;
 charger_desc->type = POWER_SUPPLY_TYPE_MAINS;
 charger_desc->properties = lt3651_charger_properties;
 charger_desc->num_properties = ARRAY_SIZE(lt3651_charger_properties);
 charger_desc->get_property = lt3651_charger_get_property;
 psy_cfg.fwnode = dev_fwnode(&pdev->dev);
 psy_cfg.drv_data = lt3651_charger;

 lt3651_charger->charger = devm_power_supply_register(&pdev->dev,
            charger_desc, &psy_cfg);
 if (IS_ERR(lt3651_charger->charger)) {
  ret = PTR_ERR(lt3651_charger->charger);
  dev_err(&pdev->dev, "Failed to register power supply: %d\n",
   ret);
  return ret;
 }

 /*
 * Acquire IRQs for the GPIO pins if possible. If the system does not
 * support IRQs on these pins, userspace will have to poll the sysfs
 * files manually.
 */
 if (lt3651_charger->acpr_gpio) {
  ret = gpiod_to_irq(lt3651_charger->acpr_gpio);
  if (ret >= 0)
   ret = devm_request_any_context_irq(&pdev->dev, ret,
    lt3651_charger_irq,
    IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
    dev_name(&pdev->dev), lt3651_charger->charger);
  if (ret < 0)
   dev_warn(&pdev->dev, "Failed to request acpr irq\n");
 }
 if (lt3651_charger->fault_gpio) {
  ret = gpiod_to_irq(lt3651_charger->fault_gpio);
  if (ret >= 0)
   ret = devm_request_any_context_irq(&pdev->dev, ret,
    lt3651_charger_irq,
    IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
    dev_name(&pdev->dev), lt3651_charger->charger);
  if (ret < 0)
   dev_warn(&pdev->dev, "Failed to request fault irq\n");
 }
 if (lt3651_charger->chrg_gpio) {
  ret = gpiod_to_irq(lt3651_charger->chrg_gpio);
  if (ret >= 0)
   ret = devm_request_any_context_irq(&pdev->dev, ret,
    lt3651_charger_irq,
    IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
    dev_name(&pdev->dev), lt3651_charger->charger);
  if (ret < 0)
   dev_warn(&pdev->dev, "Failed to request chrg irq\n");
 }

 platform_set_drvdata(pdev, lt3651_charger);

 return 0;
}

static const struct of_device_id lt3651_charger_match[] = {
 { .compatible = "lltc,ltc3651-charger" }, /* DEPRECATED */
 { .compatible = "lltc,lt3651-charger" },
 { }
};
MODULE_DEVICE_TABLE(of, lt3651_charger_match);

static struct platform_driver lt3651_charger_driver = {
 .probe = lt3651_charger_probe,
 .driver = {
  .name = "lt3651-charger",
  .of_match_table = lt3651_charger_match,
 },
};

module_platform_driver(lt3651_charger_driver);

MODULE_AUTHOR("Mike Looijmans ");
MODULE_DESCRIPTION("Driver for LT3651 charger");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:lt3651-charger");